Hair treatment, including hair coloring, is an ancient art. The oldest available records show that women then, as now, were not satisfied with their natural hair coloring and used available materials in an attempt to obtain a hair color which they considered more desirable than nature had provided. Among other coloring materials that were used aciently are henna, a red vegetable dye; indigo; sage; and camomile. Dark haired women in the time of Rome's zenith, who admired the blonde hair of female slaves brought from northern Europe, used saffron, red arsenic, nut shells and plant ash to bleach their hair. Later it was found that if the hair was wet with soap and exposed to the sun it would lighten. Mixtures of alum, black sulfur and honey have also been used as lightening agents. In the latter part of the 19th century synthetic dyes, particularly paraphenylenediamine, were developed and offered for hair coloring, either alone or in admixture with metallic salts. Oxidizing agents, particularly hydrogen peroxide, came into rather widespread use as the bleaching agent to lighten hair.
Until relatively recent times little was known and understood about the structure of hair and the mechanics of hair coloring. Through microscopic study of the hair it has been determined that a typical hair shaft, the part of the hair outside the hair follicle where the hair is formed, comprises an outer sheath of scales called the cuticle, the main body of the hair called the cortex and a slender central filament called the medulla.
The scales of the cuticle are plate-like in shape and cover the cortex somewhat in the same general manner that shingles cover a roof where the root of the hair corresponds to the ridge and the end of the hair corresponds to the eaves. This arrangement of the scales permits the hair to be combed from the scalp outward without damage to the cuticle, just as water can flow down a roof that is well shingled without causing leakage, whereas brushing or combing the hair toward the scalp tends to damage the cuticle just as a stream of water directed upwardly on a roof could easily cause leakage by penetration between the shingles and, if the force of the upwardly directed stream is strong enough, the shingles could be lifted and even torn from the roof. Being transparent, and colorless, the scale cells of the cuticle are not altered in color by bleaching agents but they must be altered structurally so as to permit the coloring solutions to pass through the cuticle and penetrate the cortex and the cuticle may be subjected to damage if the treating liquids are improperly used.
The cortex is composed of elongated cells, rather typical of fibers, comprised of complex proteins among which all the pigments that give the hair its color are found. Pigments are of different colors, such as yellow, red, brown, black, etc., and in general a hair shaft will contain pigment cells of several different colors. Pigments of different colors are affected differently by bleach and lightening solutions. In general such solutions attack the darker colors first and it has been found useful to divide the bleaching or lightening process from black to very light hair in stages which are referred to as follows:
Stage 1--black PA0 Stage 2--brown PA0 Stage 3--red PA0 Stage 4--red-gold PA0 Stage 5--gold PA0 Stage 6--yellow PA0 Stage 7--pale yellow PA0 Stage 8--white
Bleaching and lightening liquids, however, affect not only the pigment cells but also other cells of the hair and some chemical bleachants under some conditions may have a variety of adverse effects on the structural part of the hair, e.g., seriously weaken or embrittle the hair so that it will break off in wet or dry condition; cause hair to lose its normal springiness or resilience when highly bleached (to Stage 7 or 8) so that in wet condition it feels like sponge or rubber, will stretch like a thin rubber filament if pulled, will break if stretched beyond the elastic limit, and in dry condition it is brittle and snaps off if bent; and reduce the ability of the hair to take up color in the normal manner. In many cases the scalp may also be deleteriously affected by contact for too long a period of time with the bleachants used on the hair.
The medulla is not always present and is of little importance in coloring and otherwise treating the hair.
Hair coloring of the permanent type as practiced today may be carried out
(a) in two operations which are frequently referred to as (1) bleaching or prelightening and (2) tinting or coloring, or
(b) in some cases, in a single operation which comprises bleaching or lightening the natural pigments and simultaneously depositing other pigments in the cortex of the hair.
The one step process was not introduced in the market place until about 1950 after which it became very popular but it has not completely displaced the two step process which is still necessary if a person desires to change the color of the hair through several stages of lightening.
Permanent hair coloring is somewhat of a misnomer because no known process of hair coloring is able to affect the natural color of new hair that grows out after a so-called permanent color is applied. The word "permanent" as used in this art means only that the color which is applied to the then existing shaft of the hair is not washed out with shampoo and water. The most popular way of obtaining permanent hair coloring is by the use of penetrating tints or dyes which deposite pigment in the cortex of the hair shaft. It is possible, however, to apply a coating tint on the cuticle layer but this produces an unnatural look that most persons consider far less satisfactory than the appearance obtained by the use of a penetrating tint.
Semipermanent hair coloring differs from the permanent type in that it will wash out but requires several shampooings before all the color is removed. It is used primarily either to color gray hair without changing the color of the remaining pigmented hair or to make gray hair a color that the person prefers to the natural gray. In general the coloring materials used to obtain semipermanent hair coloring are the penetrating type but they are gentler on the tissues and require no peroxide developer.
Temporary hair colorings differ from the permanent and semipermanent colorings in that they deposit color on the cuticle of the hair shaft, have no lasting effect on the hair color and are washed out by shampooing. In general temporary hair coloring materials are either rinses, highlighting shampoos or materials that can be applied to the hair in the form of powders, creams, or sprays.
Hair treating materials that are applied to the hair as a liquid may be any of these types:
(a) a single material which is normally liquid within the temperature range used for hair treating,
(b) a solution of one or more materials in a liquid vehicle, including coloidal solutions, emulsions of one liquid in another, or
(c) suspensions of a finely divided solid material in a carrier liquid.
These materials have various viscosities and flow rates that may vary with temperature.
There are two general ways in which liquids are applied to the hair to be treated. One may be called an all-over application process of which coloring shampoos and rinses are typical examples. This method has been used satisfactorily for certain types of hair treating materials which are relatively nonirritating to the scalp, nondamaging to the hair and which do not have critical time periods that must be observed in order to get satisfactory results. Many hair treating materials do not satisfy these criteria and are therefore applied in the other method which may be called a step-wise or progressive method, i.e., the treating liquid is applied successively or progressively to small sections of the hair until the entire operation of treating the entire head of hair therewith has been completed. The present invention is intended for use primarily in this other method, i.e., the progressive application of hair treating liquids. Various methods are already known for effecting this progressive application of a hair treating liquid to the hair. Beginning some four decades ago color was first applied with a swab. This was followed by the bowl and brush method in which the liquid to be applied was prepared in an open bowl and applied by means of a brush that was dipped into the liquid in the bowl and then moved to the section of the hair that was ready to receive the liquid where it was applied by brush strokes primarily in the direction from the scalp toward the ends of the hair. These methods were relatively slow and time consuming and with hair treating materials that were unstable in an open bowl it was necessary frequently to prepare fresh solution, e.g., even an experienced operator working at efficient speed had to mix fresh solutions two or more times in the treatment of a single head of hair while inexperienced operators working at less efficient speed had to mix fresh solutions more times. A major improvement in application of hair treating liquids to the hair came with the use of a squeeze bottle having an externally threaded cylindrical neck on which a sectioning and dispensing attachment or applicator is screwed. This attachment comprises a body having an internally threaded cylinder or collar to be screwed on the neck of a squeeze bottle projecting outwardly in one direction and an elongated projection extending outwardly in the opposite direction, e.g., a frustum of a cone or the like, having a tapered passageway for liquid passing completely through it. The hollow projection is referred to in the art variously, e.g., as a tip or knife. A bottle and attachment of this type is shown in Levie U.S. Pat. No. 2,794,440 for hair waving solutions. An operator is able to form successive sections of a customer's hair with such a device by holding the squeeze bottle as a handle and using the tip in the same way that a rattail comb is used, although Levie shows the use of a rattail comb anyway. Such a section of the hair, which may be about 1 to 3 or 4 inches wide and ordinarily not more than about 1/8 inch thick, is referred to variously in the art as a lock, strand or tress of hair. After the operator has formed such a strand of hair in this way, it is held taut by one hand while the other hand squeezes the bottle to force a thin stream of liquid through the tip onto the scalp along the near part line of the strand at the area to be treated. In carrying out a maintenance or touch-up treatment, for example, where the root area of the hair has grown out since the last hair treatment and now requires coloring to match the existing color of the remainder of the hair, the thin stream of liquid at the part line must next be spread evenly and uniformly on only the new growth, which is a difficult operation requiring great skill with known tools and techniques because if "overlapping" of treating liquid onto the previously colored hair occurs it may result in hair breakage in the overlap area, nonuniform coloring which may persist until the hair has fully grown out, and other disadvantages. The smooth tip of the applicator is worthless as a spreading device, or as a device to pick up excess dripping material near the hairline, so most operators effect the spreading and pick-up of the liquid squeezed out of the applicator with the thumb of the hand that holds the strand of hair being treated. This strand should be kept taut while the treating liquid is spread over the root area in order to control the extent of the spread to new growth only, but this is not possible when the thumb of the same hand is used to spread the liquid, particularly if the hair is more than a few inches long because the ends of the hair above the place where the fingers grip the strand must be kept out of the way of the spreading operation. This cannot be accomplished if the hair is grasped close enough to the root to spread liquid with the thumb of the same hand. The thumb spreading operation has many other difficulties and disadvantages.
One is that the thumb is a very poor, inaccurate and inadequate spreading instrument. The inaccuracy and inadequacy are particularly disadvantageous in treating hair having a so-called "gold-band" which frequently occurs on a head of dark hair that has to be prebleached before toning and which is resistant to coloring or toning so that on a touch-up the root area is not the same color as the remainder of the hair. On the next touch-up if bleach is applied to both the new hair and the gold band for the same length of time the hair shafts in the gold band area are damaged and may break. If a beautician tries to spread the prebleach liquid with her thumb only on the new area and then later to extend the liquid into the gold band area so as to bring the new hair and gold band to the same bleached condition with minimum damage it is almost impossible to do it accurately so current practice is to spread it as well as possible on the new hair and the gold band, despite the adverse results.
A second example of difficulties arising from the inaccuracy and inadequacy of the thumb as a spreading tool is in the treatment of the short hair line hairs which are too short to grasp with the fingers, or even to part. Proper treatment of those hairs requires a spreading motion from the scalp outwardly but most beauticians spread the liquids by a transverse or rotary mortion of the thumb that is damaging to the hair.
A third difficulty is that when the thumb of the hand that holds the tress is used to spread the liquid, which is the only one the beautician can use without setting the squeeze bottle down, the hair tress has to be relaxed instead of being held taut in order for the thumb to reach the root area to spread the liquid.
A fourth difficulty is in treating a virgin head of hair that requires prebleaching and toning. The shaft has to be bleached either twice or for a longer time than the root area, where body temperature speeds up the rate of bleaching. In applying the bleach initially the place to start should be an inch or so away from the scalp and then be spread out to the end of the hair. Where this spreading is done by the thumb against the strand that the fingers are holding, the tress relaxes and the bleach tends to seep down to the scalp. The seepage is encouraged by the wiggling or twirling of the hair due to working of the liquid into the tress by the fingers and thumb of the operator. Then when the root area is treated, the scalp gets a second exposure to the bleach liquid while still tender from the first contact by seepage and may become so tender that it is abraded in the toning operation.
A fifth difficulty is that the operator has to wear a rubber glove at least on the hand that spreads the liquid or subject it to serious attack by prolonged exposure day after day to the relatively harsh chemicals that are used in the hair treating operations. An operator is not only subject to surface attack on the skin from the chemicals as such but also frequently the operator becomes sensitized to ingredients in the treating liquids with a resultant allergic reaction to them.
Many proposals have been made for various forms of applicators intended to overcome one or more of the disadvantages and problems mentioned above. For example, fountain brushes and other types of applicators are disclosed in prior patents, such as Holden U.S. Pat. No. 1,172,889 which has no parting tip, Battle U.S. Pat. No. 2,299,296 which has a solid tip but requires a special and expensive bottle, Gaspari U.S. Pat. No. 2,617,431 which has a comb and fountain brush on opposite sides of an applicator head but no tip and Pearson U.S. Pat. No. 2,618,275 which shows a round brush axially aligned with the bottle that makes accurate controlled application of liquids to the root area of hair from a straight part line difficult if not impossible. Pearson also suggests using a curved comb either adjacent to the base of the brush with the aligned tines arranged transversely with respect to the axis of the brush and bottle or at the opposite end of the bottle, but these cannot function as a parting and dispensing tip. Still other proposals include Meyer U.S. Pat. No. 2,819,723 which suggests using a solid tip at the end of a device including a fountain brush and fountain comb from which a mixture of latent dye and activator from separate containers can be dispensed selectively, Stanford U.S. Pat. No. 2,956,570, which is somewhat similar to Meyer except it suggests only a single container and a fountain comb, and Di Vito, which is similar to Stanford except that it suggests that the tip may be hollow to serve also as an applicator but discloses no means to control flow selectively to tip or comb. A further suggestion is made in McDougall-Kaley U.S. Pat. No. 3,204,644 of providing a solid tip extending laterally from the axis of a bulbous reservoir and a fountain roller at the top to apply liquid across the root area of a strand of hair adjacent to the scalp. Such a roller cannot be used satisfactorily to treat hair in which the length of new growth is less than the axial length of the roller and it is not suitable for applying liquid to the shaft of strands of hair from the root area at the scalp out to the ends which is necessary with virgin heads of hair, with heads of hair that are to be colored to a new shade or tint, and with heads of treated hair for which maintenance has been delayed too long. With the exception of the squeeze bottle and simple hollow tip applicator of the type illustrated in the Levie patent in which the tip is aligned with the axis of the bottle or displaced therefrom by an acute angle of up to at most about 30.degree., none of these devices within applicant's almost two decades of experience in commercial beauty salons has ever come to her attention except as a result of searches made in connection with her present invention. They clearly demonstrate, however, the wide spread but unfulfilled need in the art for a hair treatment device that overcomes the disadvantages and problems mentioned above and which provides an efficient, convenient, attractive, and relatively inexpensive hair treating device for conventional squeeze bottles containing hair treating liquids.
As described above, the use of a squeeze bottle and tip applicator improved the application of liquids to the hair but difficulties with mixing some materials that have to be kept apart until just before application persist. For example, bleach liquids frequently are mixtures of a liquid with finely divided powder that is injurious to eyes and detrimental if inhaled. A very recently introduced package for these materials comprises a can of the powder, a bottle of the liquid, two packages of powdered protinator, and a plastic stirrer in a mixing bowl. The can contains a warning to open it pointed away from the eyes and not to inhale the inevitable dust as it is emptied into the bowl for mixing with the liquid (and optionally also with protinator). The mixture then has to be applied with the stirrer, or put into a squeeze bottle for application. No better way has been known or used in the hair treating field.